Polymer article and method for selective metallization of the same

ABSTRACT

A method for selective metallization of a surface of a polymer article is provided. The polymer article contains a base polymer and at least one metal compound dispersed in the base polymer. The method includes gasifying at least a part of a surface of the polymer article by irradiating the surface with an energy source, and forming at least one metal layer on the surface of the polymer article by chemical plating. The metal compound contains a tin oxide doped with at least one doping element selected from a group including: V, Sb, In, and Mo.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and benefits of Chinese Patent Application Nos. 201310196611.3 and 201310195129.8, both filed with the State Intellectual Property Office of P. R. China on May 23, 2013. The entire contents of the above-referenced applications are incorporated herein by reference.

FIELD

The present disclosure relates to a surface metallization of polymer, particularly to a polymer article and a method for surface metallization of a surface of a polymer article.

BACKGROUND

Providing a metal layer on a selected area of a surface of a polymer substrate in order to form a passage for transmitting electro-magnetic signals is widely applied in the field of automobile, computer, communications, and so on. The metal layer can be formed on the surface of the polymer substrate in various ways.

For example, U.S. Pat. No. 5,599,592 discloses a metallization process for metallizing a plastic composite article containing a polymer and grains of one or more metal oxides. The method includes steps of: 1) irradiating the plastic article surface to be metallized with a light beam emitted by an excimer laser; 2) immersing the irradiated article into at least one autocatalytic bath; 3) thermally processing the metallized plastic article to induce the diffusion of the deposited metal into the plastic article. The metal oxides may be oxides of antimony, aluminum, iron, zinc or tin. It is disclosed in U.S. Pat. No. 5,599,592 that the content of the grains of metal oxides in the plastic composite article can be in the range of 1% to 30% (by weight). However, as described in embodiments of the specification of U.S. Pat. No. 5,599,592, the contents of the grains of the metal oxides in the plastic composite article are all above 4% by volume.

SUMMARY

Embodiments of the present disclosure seek to solve at least one of the problems existing in the prior art to at least some extent, or to provide a consumer with a useful commercial choice.

Embodiments of the present disclosure provide a method for selective metallization of a surface of a polymer article. The polymer article may contain a base polymer and at least one metal compound dispersed in the base polymer. The method may include steps of: gasifying at least a part of a surface of the polymer article by irradiating the surface with an energy source; and forming at least one metal layer on the surface of the polymer article by chemical plating. In some embodiments, based on the total weight of the polymer article, the content of the metal compound ranges from about 1 wt % to about 3 wt %, the content of the base polymer ranges from about 97 wt % to about 99 wt %. In some embodiments, the metal compound contains a tin oxide doped with at least one doping element selected from a group including: V, Sb, In and Mo. In some embodiments, based on the total amount of the metal compound, the content of the tin oxide ranges from about 90 mol % to about 99 mol %, and the doping element is in a form of oxide and the oxide of the doping element ranges from about 1 mol % to about 10 mol %.

According to embodiments of the present disclosure, the metal compound has a light color. When the metal compound is dispersed in the base polymer, it may not or substantially not influence the color of the base polymer itself. In addition, the metal compound has very strong adsorption power to the energy source, therefore a predetermined part of the polymer article may be removed with the irradiation of the energy source, even when the content of the metal compound is relatively low. In this way, high content of metal compound dispersed in the base polymer, which will have severe consequence on the mechanical properties of the base polymer, may be efficiently avoided.

According to embodiments of the present disclosure, the metal compound may act as an accelerator for chemical plating without being reduced to pure metal. In some embodiments, it only needs to subject the polymer article to some simple surface treatments, e.g. surface roughening, so that selective metallization on the surface of the polymer article may be achieved. In some embodiments, the surface roughening may be performed by irradiating the surface of the polymer article with a laser. The energy of the laser only needs to be sufficient for removing the predetermined part of the polymer article and exposing the metal compound in the predetermined surface, and it needs not to be extremely high in order to reduce the metal compound into pure metal. When the metal compound is exposed, the following chemical plating may be performed directly on the irradiated surface of the polymer article. The method for selective metallization of the polymer article is simple and has low requirements on the energy, therefore suitable for large scale applications.

Embodiments of the present disclosure provide a polymer article. The polymer article contains: a base polymer and at least one metal compound dispersed in the base polymer. In some embodiments, based on the total weight of the polymer article, the content of the metal compound ranges from about 1 wt % to about 3 wt %. In some embodiments, the metal compound contains a tin oxide doped with at least one doping element selected from a group including: V, Sb, In and Mo. In some embodiments, based on the total amount of the metal compound, the content of the tin oxide ranges from about 90 mol % to about 99 mol %, and the doping element is in a form of oxide and the oxide of the doping element ranges from about 1 mol % to about 10 mol %.

According to embodiments of the present disclosure, the metal compound may have a light color and may not or substantially not influence the color of the polymer article itself. Then the polymer article can have relative lighter colors as well. Such an arrangement allows creating polymer articles for special applications where polymer articles having lighter colors are required. In addition, the metal compound has very strong adsorption power to the energy source. Therefore the polymer article may be used as a polymer substrate for selective metallization, without the requirement of extremely high energy to reduce the metal compound into pure metals as required in the conventional process. A predetermined part of the polymer article may be removed with the irradiation of the energy source, even when the content of the metal compound is relatively low. In this way, high content of metal compound dispersed in the base polymer, which will have severe consequence on the mechanical properties of the base polymer, may be efficiently avoided.

Additional aspects and advantages of embodiments of present disclosure will be given in part in the following descriptions, become apparent in part from the following descriptions, or be learned from the practice of the embodiments of the present disclosure.

DETAILED DESCRIPTION

Reference will be made in detail to embodiments of the present disclosure. The embodiments described herein with reference to drawings are explanatory, illustrative, and used to generally understand the present disclosure. The embodiments shall not be construed to limit the present disclosure.

For the purpose of the present description and of the following claims, the definitions of the numerical ranges always include the extremes unless otherwise specified.

According to embodiments of an aspect of the present disclosure, a polymer article is provided. The polymer article may contain: a base polymer and at least one metal compound dispersed in the base polymer.

In some embodiments, based on the total weight of the polymer article, the content of the metal compound ranges from about 1 wt % to about 3 wt %, the content of the base polymer ranges from about 97 wt % to about 99 wt %.

In some embodiments, the metal compound may contain a tin oxide doped with at least one doping element selected from a group including: V, Sb, In and Mo. In some embodiments, the doping element is selected from V and/or Mo. In some embodiments, the doping element is selected from In and/or Sb. In some embodiments, the doping element is selected from In and/or Sb as well as at least one selected from V and Mo.

In some embodiments, the metal compound contains an oxide of In, an oxide of Sb, an oxide of V, and an oxide of Mo, and the ratio between the total amount of oxides of In and Sb and the total amount of oxides of V and Mo may be in the range of 1:1-0.1. In some embodiments, the ratio may be in the range of 1:0.5-0.2.

According to embodiments of the present disclosure, the doping element may be in the form of oxide in the metal compound. In some embodiments, based on the total amount of the metal compound (for example, the sum of the amount of the tin oxide and the amount of the oxide of the doping element), the content of the tin oxide ranges from about 90 mol % to about 99 mol %, and the oxide of the doping element ranges from about 1 mol % to about 10 mol %.

In other words, the amount of the doping element is about 1 mol % to about 10 mol %, and the amount of the doping element is obtained by the following formula:

molar amount of the oxide of the doping element/(molar amount of the oxide of the doping element+molar amount of the tin oxide).

In some embodiments, the content of the tin oxide ranges from about 92 mol % to about 98 mol %, and the oxide of the doping element ranges from about 2 mol % to about 8 mol %.

The diameter of the metal compound may be any normal option in the related art. In some embodiments, the metal compound may have a volume average diameter ranging from about 50 nm to about 10 μm. In some embodiments, the metal compound may have a volume average diameter ranging from about 300 nm to about 5 μm. In some embodiments, the metal compound may have a volume average diameter ranging from about 1 μm to about 3.5 μm. The volume average diameter may be determined by a laser particle analyzer.

According to some embodiments of the present disclosure, the metal compound may have a light color. In an embodiment, the metal compound is white.

The metal compound may be obtained by any conventional method which is known in the art. In some embodiments, the metal compound may be formed by sintering powders of the tin oxide and a compound, and the compound includes the at least one doping element. In some embodiments, the method further includes forming the metal compound by sintering powders of the tin oxide and a compound, wherein the compound comprises the at least one doping element.

The compound may be oxides of the doping elements and/or a compound precursor which is capable of forming the oxides of the doping element via the sintering step. In some embodiments, the oxides may be any normal compound formed by the doping element and oxygen. For example, the oxide may be selected from: V₂O₅, Sb₂O₃, In₂O₃ and MoO₃. The compound precursor may be hydroxides of the doping elements and/or gels of the doping elements, for example, at least one selected from a group consisting of: V hydroxide, gel containing V, Sb hydroxide, gel containing Sb, In hydroxide, gel containing In, Mo hydroxide and gel containing Mo.

In some embodiments, the compound may be selected from a group consisting of: V₂O₅, Sb₂O₃, In₂O₃ and MoO₃.

There are no special limits for the composition of the powders of the tin oxide and the compound, provided that the contents of the tin oxide and the doping element in the prepared polymer article are consistent with those described above.

There are no special limits for the diameter of the powders, which may be normal options in the related art. In some embodiment, the powders of the tin oxide and the compound have an average particle diameter ranging from about 50 nm to about 10 μm.

There are no special limits for the method for preparing the powder of the tin oxide and the compound, which may be any normal option in the related art. In some embodiments, the powders may be obtained by grinding the tin oxide and the compound containing the doping element. The grinding may be performed by a dry grinding process, a wet grinding process, or a semi-dry grinding process.

In some embodiments, the wet grinding process may be carried out using a dispersant. The dispersant may be any normally used dispersant in a conventional grinding process. In some embodiments, the dispersant may be water and/or C₁-C₅ alcohol, for example, ethanol. The amount of the dispersant is known in the art.

In some embodiments, the powders may be obtained by a wet grinding process or a semi-dry grinding process. The wet grinding process and the semi-dry grinding process may further include a drying step. The drying may be carried out with a normal drying process. In some embodiments, the drying is carried out at a temperature ranging from about 40° C. to about 120° C. In some embodiments, the drying may be carried out under an atmosphere containing oxygen, or under a non-reactive atmosphere. In some embodiments, the atmosphere containing oxygen may be air or a combination of oxygen and a non-reactive gas. The non-reactive gas may refer to any gas which may not react chemically with the components of the powders or the prepared metal compound. For example, the non-reactive gas may be those selected from group 0 of the periodic table or nitrogen. In some embodiment, the non-reactive gas may be argon.

In some embodiments, the sintering may be conducted at a temperature ranging from about 800° C. to about 1000° C. In some embodiments, the sintering may be conducted at a temperature ranging from about 850° C. to about 950° C. The condition for sintering may be selected according to the sintering temperature, and the sintering may be performed for a time period ranging from about 1 hour to 6 hours.

In some embodiments, the sintering may be carried out under an atmosphere containing oxygen. In some embodiments, the sintering may be carried out under a non-reactive atmosphere. In an embodiment, the compound may form an oxide precursor via sintering, and the sintering is performed under the atmosphere containing oxygen.

In some embodiments, the sintered powders may be subjected to a second grinding step. Therefore, the particle diameter of the further sintered powder may be further reduced and the metal compound may satisfy the following application requirements. In some embodiments, with the two sintering steps, the metal compound may have a volume average diameter ranging from about 50 nm to about 10 μm. In some embodiments, the metal compound may have a volume average diameter ranging from about 300 nm to about 5 μm. In some embodiments, the metal compound may have a volume average diameter ranging from about 1 μm to about 3.5 μm. The further grinding may be performed by at least one process selected from a group including: a dry grinding process, a wet grinding process, and a semi-dry grinding process.

In some embodiments, the further grinding process may be carried out by using a dispersant. The dispersant may be of any normal option in a conventional grinding process. In an embodiment, the dispersant may be water and/or C₁-C₅ alcohol, for example, ethanol. The amount of dispersant may be of any normal options in the art.

In some embodiments, based on the total weight of the polymer article, the content of the metal compound may vary from about 1 wt % to about 3 wt %. With this amount of metal compound dispersed in the base polymer, the polymer article may maintain an excellent mechanical performance of the base polymer, especially compact toughness. In addition, when the polymer article is irradiated with an energy source in order to remove a portion of the polymer and expose the metal compound, the metal compound may act as a chemical plating accelerator.

In some embodiments, the base polymer may be any conventional molded polymers known to those having ordinary skill in the art, and may be chosen according to practical use. In some embodiments, the base polymer may be a thermoplastic polymer or a thermosetting polymer. In an embodiment, the base polymer may be at least one selected from a group including: plastic, rubber, and fiber.

By way of example and without limits, in some embodiments the polymer may be at least one selected from a group including: polyolefin, such as polystyrene, polypropylene, poly(methyl methacrylate), poly(acrylonitrile-butadiene-styrene); polycarbonate; polyester, such as poly(cyclohexyl-paradimethylene terephthalate), poly(diallyl isophthalate), poly(diallyl teraphthalate), poly(butylene naphthalate), poly(ethylene terephthalate), poly(butylene terephthalate); polyamide, such as poly(hexamethylene adipamide), poly(hexamethylene azelamide), poly(hexamethylene succinamide), poly(hexamethylene lauramide), poly(hexamethylene sebacamide), poly(decamethylene sebacamide), poly(undecanoic amide), poly(lauramide), poly(octanamide), poly(9-arninononanoic acid), polycaprolactam, poly(paraphenylene phthalamide), poly(isophenylene phthalamide), poly(paraphenylene adipamide), poly(paraphenylene azelamide); poly(aromatic ether); polyether imide; polycarbonate/(acrylonitrile-butadiene-styrene) alloy; polyphenylene oxide; polyphenylene sulfide; polyimide; polysulfone; poly(ether-ether-ketone); polybenzimidazole; phenol formaldehyde resin; urea formaldehyde resin; melamine-formaldehyde resin; epoxide resin; alkyd resin and polyurethane.

In some embodiments, the polymer article may further contain at least one additive. In some embodiments, the additive can be, for example, filler, antioxidant, light stabilizer and so on. By the addition of the additive, the performance and property of the polymer article may be improved. There are no special limits for the content and the type of the additive. The additive can have a light colour. The additive may be selected according to, for example, practical requirements.

The filler used as the additive to the polymer article may be any filler which is non-reactive under the effect of laser (either physically or chemically). In some embodiments, the filler may be at least one selected from tal and/or calcium carbonate.

In some embodiments, the filler may be glass fiber. With the addition of glass fiber, the thickness of the removed base polymer (in other words, the distance from the top surface of the polymer article to the exposed metal compound) may be significantly increased, which may facilitate the deposition of metal onto the metal compound during the following chemical plating process.

In some embodiments, the filler may also be selected from micro glass bead, calcium sulfate, barium sulfate, titanium dioxide, pearl powder, wollastonite, diatomite, caoline, coal fines, pot clay, mica, oil shale ash, aluminum silicate, alumina, silica and zinc oxide. In an embodiment, the filler may be titanium dioxide and the brightness of the polymer article may be further increased.

The antioxidant used as the additive to the polymer article may be any conventional antioxidant in the related art. In some embodiments, the antioxidant may contain a primary antioxidant and a secondary antioxidant. The ratio between the primary antioxidant and the secondary antioxidant may be appropriately selected according to, for example, the type of the antioxidant. In some embodiments, the weight ratio between the primary antioxidant and the secondary antioxidant may be about 1:1-4.

In some embodiments, the primary antioxidant may be a hindered phenol antioxidant. By way of example but without limits, in some embodiments, the primary antioxidant may be antioxidant 1098 or antioxidant 1010, in which the antioxidant 1098 mainly contains N,N′-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexane diamine and the antioxidant 1010 mainly contains tetra[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid]pentaerythritol.

In some embodiments, the secondary antioxidant may be a phosphite ester antioxidant. By way of example and without limits, in some embodiments, the secondary antioxidant may be antioxidant 168, which mainly contains tri(2,4-di-tert-butyl-phenyl)phosphorite.

In some embodiments, the light stabilizer used as the additive to the polymer article may be of the hindered amine type. In some embodiments, the light stabilizer may be bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate. The light stabilizer may be any known ones in the art, without special limits in the present disclosure.

In some embodiments, the amount of the additive may be appropriately selected according to functions and types of the additives. In some embodiments, based on 100 weight parts of the polymer article, the content of the filler may range from 1 weight part to 40 weight parts, the content of the antioxidant may range from about 0.01 weight parts to about 1 weight parts, the content of the light stabilizer may range from about 0.01 weight parts to about 1 weight part, and the content of the lubricant may range from about 0.01 weight parts to about 1 weight part.

In some embodiments, the polymer article may be prepared with the following steps: a mixture containing a base polymer and at least one of the above-identified metal compound is mixed to form a polymer composition, and then the composition is molded.

In some embodiments, the above-identified additive may be used to improve the performance of the base polymer and provide the base polymer with a new performance. In some embodiments, the base polymer may further contain an additive for improving the processing performance of the base polymer, such as a lubricant.

In some embodiments, the lubricant may be at least one selected from a group including: ethylene/vinyl acetate copolymer (EVA wax), polyethylene (PE wax) and stearate. With the addition of the lubricant, the flowing performance of the polymer article may be improved.

In some embodiments, the molding step may be performed by any conventional molding process known in the art, without special limits in the present disclosure. In some embodiments, the molding step is performed by injection molding. In another embodiment, the molding step is performed by extrusion molding.

Embodiments of another aspect of the present disclosure provide a method for selective metallization of a surface of a polymer article. The polymer article may contain a base polymer and at least one metal compound dispersed in the base polymer. The method may include steps of: gasifying at least a part of a surface of the polymer article by irradiating the surface with an energy source; and forming at least one metal layer on the surface of the polymer article by chemical plating. In some embodiments, based on the total weight of the polymer article, the content of the metal compound ranges from about 1 wt % to about 3 wt %, the content of the base polymer ranges from about 97 wt % to about 99 wt %. In some embodiments, the metal compound contains a tin oxide doped with at least one doping element selected from a group including: V, Sb, In and Mo. In some embodiments, based on the total amount of the metal compound, the content of the tin oxide ranges from about 90 mol % to about 99 mol %, and the doping element is in a form of oxide and the oxide of the doping element ranges from about 1 mol % to about 10 mol %.

In other words, the amount of the doping element is about 1 mol % to about 10 mol %, and the amount of the doping element is obtained by the following formula:

molar amount of the oxide of the doping element/(molar amount of the oxide of the doping element +molar amount of the tin oxide).

In some embodiments, the method for selective metallization of a surface of a polymer article may include steps of: providing a polymer composition containing a base polymer and at least one metal compound dispersed in the base polymer; forming the polymer article by molding the polymer composition; gasifying at least a part of a surface of the polymer article by irradiating the surface with an energy source; and forming at least one metal layer on the surface of the polymer article by chemical plating.

According to embodiments of the present disclosure, the base polymer in a predetermined area of the surface of the polymer article may be removed and the metal compound in the predetermined area may be exposed by the irradiating step. In the following chemical plating step, metals may be deposited on the metal compound in the predetermined area of the polymer article, by which at least one metal layer may be formed on the predetermined area of the polymer article. In this way, selective metallization of the polymer article may be achieved.

The inventors have found that, selective metallization an insulative substrate like plastic may be achieved by dispersing metal oxides into an insulative substrate, irradiating a surface of the insulative substrate to be metallized followed by chemical plating. When the metal oxide has relatively dark color, the dark color of the metal oxide may conflict with or influence the color of the insulative substrate. However, if a metal oxide having a lighter color is used, due to the poor light absorption capability of the lighter metal oxide, the energy of from the energy source cannot be absorbed efficiently by the polymer article. In this condition, the base polymer in the predetermined area of the surface of the polymer article may not be removed rapidly and completely. Worse still, a porous surface may be formed. Moreover, the active sites formed for the following chemical plating step may not be sufficient, and then the requirements for the chemical plating step may hardly met. Therefore, it is believed that the requirements for the following chemical plating (i.e. removing the base polymer in the predetermined area and forming enough active sites on the metal oxide) may be satisfied with higher amount of the metal oxide or higher energy.

The inventors have found that, the tin oxide doped with at least one doping element selected from a group including V. Sb, In and Mo may have a lighter color and stronger light absorption capability than that of a conventional tin oxide. Further, with the doped tin oxide, the base polymer in the predetermined area of the polymer article may be removed even with lower amount of the doped tin oxide. As the amount of the tin oxide is lower, negative impacts on the mechanical property of the polymer article due to high content of metal additive may be efficiently prevented. In addition, the metal compound may be used as the chemical plating accelerator (also referred as catalyst) in the following chemical plating step, without reducing the metal compound into pure metals. In other words, even the surface of the polymer article is irradiated with relatively lower energy, the chemical plating step may be performed successfully. Then the polymer article may be obtained.

The base polymer, metal compound and the polymer article are all described in details in the above, therefore detailed description thereof is omitted herein.

In some embodiments, the energy source may be at least one selected from a group including: laser, electron beam and ion beam. In an embodiment, the energy source is a laser. The energy provided by the laser must ensure the base polymer in the irradiated area of the surface of the polymer article is gasified and the metal compound in the irradiated area is exposed. The metal compound has excellent absorption capability to energy provided by the energy source, thus the base polymer in the predetermined area may be removed and the metal compound in the predetermined area may be exposed, even irradiating with the energy source which provides relatively lower energy.

In some embodiments, the gasifying step may be performed by using a laser, and the laser may have a wavelength of 157-10600 nm and a power of 1-100 W. In an embodiment, the laser may have a wavelength of 1064-10600 nm and a power of 3-50 W. In another embodiment, the laser may have a wavelength of 1064 nm and a power of 3-40 W. In a further embodiment, the laser may have a wavelength of 1064 nm and a power of 5-20 W. The predetermined area of the surface of the polymer article may form a pattern, then the metal layer formed on the predetermined area may form a metal pattern on the polymer article. With the laser, the precision of the metal pattern may be improved.

In some embodiments, the gasifying step may be performed by using an electron beam, and the electron beam may have a power density of 10-10¹¹ W/cm².

In some embodiments, the gasifying step may be performed by using an ion beam, and the ion beam may have an energy of 10-10⁶ eV.

The chemical plating is well known to person having ordinary skill in the art. In some embodiments, the chemical plating may be carried out with the following steps. The polymer article subjected to the irradiating is immersed in a Cu solution. In some embodiments, the Cu solution may contain a Cu salt. In some embodiments, the Cu solution may further contain a reducing agent. In some embodiments, the Cu solution may have a pH ranging from about 12 to about 13. In some embodiments, the reducing agent may reduce the Cu ions in the Cu salt into Cu metal. In some embodiments, the reducing agent may be at least one selected from a group including: glyoxylic acid, diamide, and sodium phosphorate.

In some embodiments, the method may further include a step of electroplating or chemical plating. The electroplating or chemical plating may be performed for at least one time, so that additional metal layers, either of the same metal as or of different metals from the prior metal layers, may be formed on the prior metal layers. In some embodiments, a Cu layer is formed on the surface of the polymer article in the first chemical plating step, then a Ni layer is formed on the Cu layer in the following electroplating or chemical plating. With the additional Ni layer, oxidation of the Cu layer may be prevented.

It will be understood that the features mentioned above and those still to be explained hereinafter may be used not only in the particular combination specified but also in other combinations or on their own, without departing from the scope of the present invention.

Some illustrative and non-limiting examples are provided hereunder for a better understanding of the present invention and its practical embodiments.

Testing Method

Samples of the metal compounds and the polymer articles obtained from the following Examples and Comparative Examples were subjected to the following tests.

Composition

In the following Examples and Comparative Examples, the composition of the metal compound was measured by an Inductively Coupled Plasma—Atomic Emission Spectrometry (ICP-AES).

Volume Average Diameter

In the following Examples and Comparative Examples, the volume average diameter of the metal compound was measured by a Laser Particle Sizer commercially available from Chengdu Jingxin Powder Analyse Instrument Co., Ltd., China.

Adhesion

In the following Examples and Comparative Examples, the adhesion between the metal layer and the base polymer was determined by a cross-cut process. Specifically, a surface of the sample to be measured was cut using a cross-cut knife to form 100 grids (1 mm×1 mm). A gap between adjacent grids was formed to reach the bottom of the metal layer. Debris in the test region was cleaned using a brush, and then an adhesive tape (3M600 gummed paper) was sticked to a tested grid. One end of the sticked adhesive paper was rapidly torn off in a vertical direction. Two identical tests were performed on the same grid region. The grade of the adhesion was determined according to the following standard:

Grade 5B: the cut edge is smooth and the metal layers both at the cut edge and cut intersection of the grid does not fall off;

Grade 4B: the metal layers at the cut intersection are partly removed, but no more than 5% (area percent) of the metal layers are removed;

Grade 3B: the metal layers both at the cut edge and the cut intersection are partly removed, and 5-15% (area percent) of the metal layers are removed;

Grade 2B: the metal layers at both the cut edge and the cut intersection are partly removed, and 15-35% (area percent) of the metal layers are removed;

Grade 1B: the metal layers at both the cut edge and the cut intersection are partly removed, and 35-65% (area percent) of the metal layers are removed;

Grade 0B: the metal layers at both the cut edge and the cut intersection are partly removed, and more than 65% (area percent) of the metal layers are removed.

The results are shown in Table 1.

Notch Impact Strength

In the following Examples and Comparative Examples, the notch impact strength of the polymer article was measured according to ASTM D256. For each sample, 5 testing points were tested and 5 results were recorded, and the value of the notch impact strength was recorded as the average of the 5 results.

Chemical Plating Accelerator

In the following Examples and Comparative Examples, the method for determining whether the metal compound can act as the chemical plating accelerator includes the following steps.

1) 50 g of the metal compound, 20 g of binder material CAB381-0.5 (commercially available from Eastman Chemical Company, US), 100 g of n-ethanol, 2 g of dispersing agent DISPERBYK-165 (commercially available from BYK Company, GE), 0.2 g of antifoaming agent BYK-051 (commercially available from BYK Company, GE), 0.4 g of leveling agent BYK-333 (commercially available from BYK Company, GE) and 0.5 g of hydrogenated castor oil (commercially available from Wuhan Jinnuo Chemical Company, China) were mixed uniformly to obtain an ink composition.

2) The ink composition obtained from the step 1) was applied on a surface of an Al₂O₃ ceramic substrate by ink jet printing, and then the Al₂O₃ ceramic substrate was dried at 120° C. for 3 hours. Then, an ink layer was formed on the surface of the Al₂O₃ ceramic substrate, which was formed as a pattern on the Al₂O₃ ceramic substrate and could be used as an antenna for a receiver.

3) The ceramic substrate obtained from the step 2) was subjected to chemical plating using a Cu solution containing: 0.12 mol/L of CuSO₄.5H₂O, 0.14 mol/L of Na₂EDTA.2H₂O, 10 mg/L of potassium ferrocyanide, 10 mg/L of 2,2′-bipyridine and 0.10 mol/L of glyoxylic acid. The Cu solution had a temperature of 50° C. and a pH ranging in 12.5-13, which is adjusted with NaOH and H₂SO₄.

Then the surface of the ceramic substrate which had been subjected to the chemical plating was observed. If metals had been deposited on the surface of the ceramic substrate and formed a complete pattern (circuit), then it is indicated that the metal compound can be used as chemical plating accelerator. If the deposited metals cannot form a complete pattern (circuit) on the surface of the ceramic substrate or even no metal is deposited on the surface of the ceramic substrate, then it is indicated that the metal compound cannot be used as chemical plating accelerator.

EXAMPLES Example 1 (E1)

1) Particles of SnO₂ were grinded in a grinding mill for 4 h together with V₂O₅ and ethanol, to form a first mixture. Based on 100 weight parts of SnO₂ and V₂O₅, the content of ethanol was 150 weight parts. Based on the total amount of SnO₂ and V₂O₅, the content of V₂O₅ was 10 mol %. The first mixture was dried under an air atmosphere at 80° C. for 2 h, thus obtaining a second mixture having a volume average particle diameter of 1 μm. The second mixture was calcined under an air atmosphere at 900° C. for 5 h and grinded to white powders having a volume average particle diameter of 1.5 μm. After tested, the white powders included doped tin oxide with a content of V₂O₅ being 10 mol %.

2) The white powders of doped tin oxide were mixed with polycarbonate (PC) to form a third mixture, and then the third mixture was extruded and pelleted with an extruder to form pellets. The pellets were injection molded in an injection mould, thus forming a PC sheet containing the doped tin oxide. Based on the total weight of the doped tin oxide and the PC, the content of the doped tin oxide was 3 wt %. The PC sheet was subjected to an impact strength test, and the results were recorded in Table 1.

3) A surface of the PC sheet was irradiated with a laser provided by a YAG laser, to remove PC on a predetermined area (corresponding to the structure of a receiver) of the surface of the PC sheet. The laser had a wavelength of 1064 nm, a power of 5 W, a frequency of 30 kHz, a scanning speed of 1000 mm/s and a filling distance of 30 μm.

4) The PC sheet obtained from the step 3) was subjected to chemical plating by using a Cu solution, thus forming a metal layer on the predetermined area of the surface of the PC sheet. The metal layer may be used as an antenna. The Cu solution contained: 0.12 mol/L of CuSO₄.5H₂O, 0.14 mol/L of Na₂EDTA. 2H₂O, 10 mg/L of potassium ferrocyanide, 10 mg/L of 2,2′-bipyridine and 0.10 mol/L of glyoxylic acid. The Cu solution had a temperature of 50° C. and a pH ranging in 12.5-13 which is adjusted with NaOH and H₂SO₄. Then the PC sheet formed with the metal layer was observed, and it was found that the metal layer formed a complete circuit on the PC sheet. The plating speed and adhesion between the metal layer and the PC were both listed in Table 1.

COMPARATIVE EXAMPLE 1 (CE1)

1) Tin oxide was mixed with PC to form a third mixture, and then the third mixture was extruded and pelleted with the same condition as described in the step 2) of Example 1, thus forming a PC sheet containing tin oxide. Based on the total weight of the tin oxide and the PC, the content of the tin oxide was 3 wt %.

2) The PC sheet obtained from the step 2) was irradiated with a laser under the same condition as described in the step 3) of Example 1.

3) The PC sheet obtained from the step 3) was subjected to a chemical plating under the same condition as described in the step 4) of Example 1. It was observed that, it was not capable of forming a complete metal circuit on the PC sheet.

COMPARATIVE EXAMPLE 2 (CE2)

1) Tin oxide was mixed with PC to form a third mixture, and then the third mixture was extruded and pelleted with the same condition as described in the step 2) of Example 1, thus forming a PC sheet containing tin oxide. Based on the total weight of the tin oxide and the PC, the content of the tin oxide was 10 wt %, i.e. 1.85 vol %. The PC sheet was subjected to an impact strength test, and the results were recorded in Table 1.

2) The PC sheet obtained from the step 2) was irradiated with a laser under the same condition as described in the step 3) of Example 1.

3) The PC sheet obtained from the step 3) was subjected to a chemical plating under the same condition as described in the step 4) of Example 1. It was observed that, a complete metal circuit was formed on the PC sheet. The plating speed and adhesion between the metal layer and the PC were both listed in Table 1.

COMPARATIVE EXAMPLE 3 (CE3)

The present example included substantially the same steps 1) to 4) as those of Example 1, with the exception that: in the step 2), based on the total weight of the doped tin oxide and the PC sheet, the content of the doped tin oxide was 5 wt %. It was observed that, a complete metal circuit was formed on the PC sheet. The plating speed, adhesion and impact strength were all listed in Table 1.

EXAMPLE 2 (E2)

1) Particles of SnO₂ were grinded in a grinding mill for 2 h together with MoO₃ and ethanol, to form a first mixture. Based on 100 weight parts of SnO₂ and MoO₃, the content of ethanol was 160 weight parts. Based on the total amount of SnO₂ and MoO₃, the content of MoO₃ was 10 mol %. The first mixture was dried under an air atmosphere at 80° C. for 3 h, thus obtaining a second mixture having a volume average particle diameter of 2.6 μm. The second mixture was calcined under an air atmosphere at 950° C. for 5 h and grinded to white powders having a volume average particle diameter of 1.6 μm. After tested, the white powders included doped tin oxide with a content of MoO₃ being 10 mol %.

2) The white powders of doped tin oxide were mixed with PC to form a third mixture, and then the third mixture was extruded and pelleted with an extruder to form pellets. The pellets were injection molded in an injection mould, thus forming a PC sheet containing the doped tin oxide. Based on the total weight of the doped tin oxide and the PC, the content of the doped tin oxide was 3 wt %. The PC sheet was subjected to an impact strength test, and the results were recorded in Table 1.

3) A surface of the PC sheet was irradiated with a laser under the same condition as described in the step 3) of Example 1.

4) The PC sheet obtained from the step 3) was subjected to chemical plating under the same condition as described in the step 4) of Example 1. Then the PC sheet formed with the metal layer was observed, and it was found that the metal layer formed a complete circuit on the PC sheet. The plating speed and adhesion between the metal layer and the PC were both listed in Table 1.

COMPARATIVE EXAMPLE 4 (CE4)

The present example included substantially the same steps 1) to 4) as those of Example 2, with the exception that: in the step 1), the same amount of Ga₂O₃ was used instead of MoO₃. It was observed that, it was not capable of forming a complete metal circuit on the PC sheet.

EXAMPLE 3 (E3)

1) The step of preparing the doped tin oxide was substantially the same with the step 1) of Example 2, with the exception that: the amount of MoO₃ was 8 mol %. After tested, the white powders was proved to be doped tin oxide with a content of MoO₃ being 8 mol %.

2) The step of preparing the PC sheet was substantially the same with the step 2) of Example 2, with the exception that: the doped tin oxide was those obtained from the step 1) of Example 3. The PC sheet was subjected to an impact strength test, and the results were recorded in Table 1.

3) The step of irradiating the PC sheet was substantially the same with the step 3) of Example 2, with the exception that: the PC sheet was obtained from the step 2) of Example 3.

4) The step of chemical plating was substantially the same with the step 4) of Example 2, with the exception that: the PC sheet was obtained from the step 3) of Example 3. The PC sheet formed with the metal layer was observed, and it was found that the metal layer formed a complete circuit on the PC sheet. The plating speed and adhesion between the metal layer and the PC were both listed in Table 1.

EXAMPLE 4 (E4)

1) Particles of SnO₂ were grinded in a grinding mill for 5 h together with V₂O₅ and ethanol, to form a first mixture. Based on 100 weight parts of SnO₂ and V₂O₅, the content of ethanol was 120 weight parts. Based on the total amount of SnO₂ and V₂O₅, the content of V₂O₅ was 1 mol %. The first mixture was dried under a nitrogen atmosphere at 100° C. for 6 h, thus obtaining a second mixture having a volume average particle diameter of 1.8 μm. The second mixture was calcined under an air atmosphere at 850° C. for 6 h and grinded to white powders having a volume average particle diameter of 1.2 μm. After tested, the white powders was proved to be doped tin oxide with a content of V₂O₅ being 1 mol %.

2) The white powders of doped tin oxide were mixed with PC to form a third mixture, and then the third mixture was extruded and pelleted with an extruder to form pellets. The pellets were injection molded in an injection mould, thus forming a PC sheet containing the doped tin oxide. Based on the total weight of the doped tin oxide and the PC, the content of the doped tin oxide was 3 wt %. The PC sheet was subjected to an impact strength test, and the results were recorded in Table 1.

3) A surface of the PC sheet obtained from the step 2) was irradiated with a laser provided by a YAG laser, to remove PC on a predetermined area (corresponding to the structure of a receiver) of the surface of the PC sheet. The laser had a wavelength of 1064 nm, a power of 20 W, a frequency of 30 kHz, a scanning speed of 800 mm/s and a filling distance of 25 μm.

4) The PC sheet obtained from the step 3) was subjected to chemical plating under the same condition as described in the step 4) of Example 1. Then the PC sheet formed with the metal layer was observed, and it was found that the metal layer formed a complete circuit on the PC sheet. The plating speed and adhesion between the metal layer and the PC were both listed in Table 1.

EXAMPLE 5 (E5)

1) The step of preparing the doped tin oxide was substantially the same with the step 1) of Example 4, with the exception that: the amount of V₂O₅ was 2 mol %. After tested, the white powders was proved to be doped tin oxide with a content of V₂O₅ being 2 mol %.

2) The step of preparing the PC sheet was substantially the same with the step 2) of Example 4, with the exception that: the doped tin oxide was those obtained from the step 1) of Example 5. The PC sheet was subjected to an impact strength test, and the results were recorded in Table 1.

3) The step of irradiating the PC sheet was substantially the same with the step 3) of Example 4, with the exception that: the PC sheet was obtained from the step 2) of Example 5.

4) The step of chemical plating was substantially the same with the step 4) of Example 4, with the exception that: the PC sheet was obtained from the step 3) of Example 5. The PC sheet formed with the metal layer was observed, and it was found that the metal layer formed a complete circuit on the PC sheet. The plating speed and adhesion between the metal layer and the PC were both listed in Table 1.

EXAMPLE 6 (E6)

1) Particles of Sn0₂ were grinded in a grinding mill for 4 h together with MoO₃, V₂O₅ and ethanol, to form a first mixture. Based on 100 weight parts of SnO₂, MoO₃ and V₂O₅, the content of ethanol was 200 weight parts. Based on the total amount of SnO₂, MoO₃ and V₂O₅, the content of MoO₃ was 1.8 mol %, the content of V₂O₅ was 2.5 mol %. The first mixture was dried under an air atmosphere at 120° C. for 4 h, thus obtaining a second mixture having a volume average particle diameter of 3.8 m. The second mixture was calcined under an air atmosphere at 920° C. for 4 h and grinded to white powders having a volume average particle diameter of 3.2 μm. After tested, the white powders was proved to be doped tin oxide with a content of MoO₃ being 1.8 mol % and a content of V₂O₅ being 2.5 mol %.

2) The white powders obtained from the step 1) were mixed with PC and TiO₂ (having a volume average diameter of 2.1 μm) to form a third mixture, and then the third mixture was extruded and pelleted with an extruder to form pellets. The pellets were injection molded in an injection mould, thus forming a PC sheet containing the doped tin oxide. Based on the total weight of the doped tin oxide, TiO₂ and the PC, the content of the doped tin oxide was 1.8 wt %, the content of the TiO₂ was 2 wt %. The PC sheet was subjected to an impact strength test, and the results were recorded in Table 1.

3) The PC sheet obtained from the step 2) was irradiated with a laser under the same condition as described in the step 3) of Example 1.

4) The PC sheet obtained from the step 3) was subjected to chemical plating under the same condition as described in the step 4) of Example 1. Then the PC sheet formed with the metal layer was observed, and it was found that the metal layer formed a complete circuit on the PC sheet. The plating speed and adhesion between the metal layer and the PC were both listed in Table 1.

EXAMPLE 7 (E7)

The present example included substantially the same steps 1) to 4) as those of Example 1, with the exception that: in the step 1), the same amount of In₂O₃ was used instead of V₂O₅. It was found that the metal layer formed a complete circuit on the PC sheet. The plating speed and adhesion between the metal layer and the PC were both listed in Table 1.

EXAMPLE 8 (E8)

The present example included substantially the same steps 1) to 4) as those of Example 1, with the exception that: in the step 1), the same amount of Sb₂O₃ was used instead of V₂O₅. It was found that the metal layer formed a complete circuit on the PC sheet. The plating speed and adhesion between the metal layer and the PC were both listed in Table 1.

EXAMPLE 9 (E9)

1) Particles of SnO₂ were grinded in a grinding mill for 4 h together with MoO₃, Sb₂O₃ and ethanol, to form a first mixture. Based on 100 weight parts of SnO₂, Sb₂O₃ and V₂O₅, the content of ethanol was 200 weight parts. Based on the total amount of SnO₂, Sb₂O₃ and V₂O₅, the content of MoO₃ was 1.2 mol %, the content of Sb₂O₃ was 5.6 mol %. The first mixture was dried under an air atmosphere at 80° C. for 4 h, thus obtaining a second mixture having a volume average particle diameter of 3.1 μm. The second mixture was calcined under an air atmosphere at 920° C. for 4 h and grinded to white powders having a volume average particle diameter of 2.6 μm. After tested, the white powders was proved to be doped tin oxide with a content of MoO₃ being 1.2 mol % and a content of Sb₂O₃ being 5.6 mol %.

2) The white powders obtained from the step 1) were mixed with PC to form a third mixture, and then the third mixture was extruded and pelleted with an extruder to form pellets. The pellets were injection molded in an injection mould, thus forming a PC sheet containing the doped tin oxide. Based on the total weight of the doped tin oxide and the PC, the content of the doped tin oxide was 2.8 wt %. The PC sheet was subjected to an impact strength test, and the results were recorded in Table 1.

3) The PC sheet obtained from the step 2) was irradiated with a laser under the same condition as described in the step 3) of Example 1.

4) The PC sheet obtained from the step 3) was subjected to chemical plating under the same condition as described in the step 4) of Example 1. Then the PC sheet formed with the metal layer was observed, and it was found that the metal layer formed a complete circuit on the PC sheet. The plating speed and adhesion between the metal layer and the PC were both listed in Table 1.

EXAMPLE 10 (E 10)

1) Particles of SnO₂ were grinded in a grinding mill for 4 h together with MoO₃, In₂O₃ and ethanol, to form a first mixture. Based on 100 weight parts of SnO₂, MoO₃ and In₂O₃, the content of ethanol was 200 weight parts. Based on the total amount of SnO₂, MoO₃ and In₂O₃, the content of MoO₃ was 1.8 mol %, the content of In₂O₃ was 6.9 mol %. The first mixture was dried under an air atmosphere at 120° C. for 4 h, thus obtaining a second mixture having a volume average particle diameter of 4.2 μm. The second mixture was calcined under an air atmosphere at 900° C. for 6 h and grinded to white powders having a volume average particle diameter of 2.5 μm. After tested, the white powders was proved to be doped tin oxide with a content of MoO₃ being 1.8 mol % and a content of In₂O₃ being 6.9 mol %.

2) The white powders obtained from the step 1) were mixed with PC to form a third mixture, and then the third mixture was extruded and pelleted with an extruder to form pellets. The pellets were injection molded in an injection mould, thus forming a PC sheet containing the doped tin oxide. Based on the total weight of the doped tin oxide and the PC, the content of the doped tin oxide was 2.6 wt %. The PC sheet was subjected to an impact strength test, and the results were recorded in Table 1.

3) The PC sheet obtained from the step 2) was irradiated with a laser under the same condition as described in the step 3) of Example 1.

4) The PC sheet obtained from the step 3) was subjected to chemical plating under the same condition as described in the step 4) of Example 1. Then the PC sheet formed with the metal layer was observed, and it was found that the metal layer formed a complete circuit on the PC sheet. The plating speed and adhesion between the metal layer and the PC were both listed in Table 1.

TABLE 1 Whether can Plating speed Impact Strength be used (μm/h) Adhesion (J/m) as accelerators E1 5.1 5B 673.8 Yes CE1 — — — No CE2 6.0 5B 483.0 — CE3 5.6 5B 548.4 — E2 5.2 5B 650.2 Yes CE4 — — — No E3 5.1 5B 649.3 Yes E4 2.7 3B 676.4 Yes E5 3.8 4B 679.3 Yes E6 4.7 5B 642.3 Yes E7 2.6 4B 659.4 Yes E8 2.4 4B 661.2 Yes E9 4.2 5B 658.1 Yes E10 4.1 5B 684.2 Yes

Reference throughout this specification to “an embodiment,” “some embodiments,” “one embodiment”, “another example,” “an example,” “a specific example,” or “some examples,” means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. Thus, the appearances of the phrases such as “in some embodiments,” “in one embodiment”, “in an embodiment”, “in another example,” “in an example,” “in a specific example,” or “in some examples,” in various places throughout this specification are not necessarily referring to the same embodiment or example of the present disclosure. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

Although explanatory embodiments have been shown and described, it would be appreciated by those skilled in the art that the above embodiments cannot be construed to limit the present disclosure, and changes, alternatives, and modifications can be made in the embodiments without departing from spirit, principles and scope of the present disclosure. 

What is claimed is:
 1. A method for selective metallization of a surface of a polymer article, wherein the polymer article comprises a base polymer and at least one metal compound dispersed in the base polymer, the method comprising: gasifying at least a part of a surface of the polymer article by irradiating the surface with an energy source; and forming at least one metal layer on the surface of the polymer article by chemical plating, wherein based on the total weight of the composition of the polymer article, the metal compound ranges from about 1 wt % to about 3 wt %, the base polymer ranges from about 97 wt % to about 99 wt %, and the metal compound comprises a tin oxide doped with at least one doping element selected from a group including: V, Sb, In, and Mo.
 2. The method according to claim 1, wherein based on the total amount of the metal compound, the tin oxide ranges from about 90 mol % to about 99 mol %, and the doping element is in a form of oxide and the oxide of the doping element ranges from about 1 mol % to about 10 mol %.
 3. The method according to claim 1, wherein the tin oxide ranges from about 92 mol % to about 98 mol %, and the oxide of the doping element ranges from about 2 mol % to about 8 mol %.
 4. The method according to claim 1, wherein the metal compound has a volume average diameter ranging from about 50 nm to about 10 μm.
 5. The method according to any of claims 1, further comprising forming the metal compound by sintering powders of the tin oxide and a compound including the at least one doping element.
 6. The method according claim 5, wherein the compound is selected from a group including: V₂O₅, Sb₂O₃, In₂O₃, and MoO₃.
 7. The method according claim 5, wherein the sintering is conducted at a temperature ranging from about 800° C. to about 1000° C.
 8. The method according to claim 1, wherein the energy source includes a laser.
 9. A polymer article comprising: a base polymer, and at least one metal compound dispersed in the base polymer, wherein based on the total weight of the polymer article the metal compound ranges from about 1 wt % to about 3 wt %; and the metal compound comprises a tin oxide doped with at least one doping element selected from a group including: V, Sb, In, and Mo.
 10. The method according to claim 9, wherein based on the total amount of the metal compound, the tin oxide ranges from about 90 mol % to about 99 mol %, and the doping element is in a form of oxide and the oxide of the doping element ranges from about 1 mol % to about 10 mol %.
 11. The polymer article according to claim 8, wherein the tin oxide ranges from about 92 mol % to about 98 mol %, and the oxide of the doping element ranges from about 2 mol % to about 8 mol %.
 12. The polymer article according to claim 9, wherein the metal compound is formed by sintering powders of the tin oxide and a compound including the at least one doping element.
 13. The polymer article according claim 10, wherein the compound is selected from a group including: V₂O₅, Sb₂O₃,1n₂O₃, and MoO₃.
 14. The polymer article according claim 12, wherein the sintering is conducted at a temperature ranging from about 800° C. to about 1000° C.
 15. The polymer article according to claim 9, wherein the metal compound has a volume average diameter ranging from about 50 nm to about 10 μm. 